1. Field of the Invention
The present invention relates to a graphical user interface. More specifically, the present disclosure relates to a method of supporting subtle user input during an input operation using a touch screen display. For example, the present disclosure relates to a method of supporting user input such that an instruction operation on a pixel level can be performed easily on a touch screen display.
2. Description of Related Art
Touch screen displays have come to be used in a variety of ways (see, for example, Japanese Patent Laid-open Publication No. H09-237157, Japanese Patent Laid-open Publication No. 2000-267808, Japanese Patent Laid-open Publication No. 2011-028524, and Japanese Patent No. 5132028). In addition, employing touch screen displays as an input device has also been explored in the field of measuring apparatuses, such as those measuring a length, outline shape, or the like of a work piece (measured object).
Touch screen displays are excellent input devices providing a user with numerous conveniences, such as being intuitive and user friendly, being capable of both display and input, having excellent portability due to being a small terminal, and the like. However, there are significant issues when performing input operations for a measuring apparatus on a touch screen display. When performing input operations for a measuring apparatus, extremely fine input instructions are often required. For example, input operations on a pixel level are becoming necessary when designating a measurement range. Accordingly, numeric values may be typed in directly, and even in cases using a GUI, fine positioning may be performed with a mouse cursor (pointer) (Japanese Patent Laid-open Publication No. H11-237221).
In this regard, a touch screen display recognizes a center of gravity of a portion pressed by a finger or stylus as an indicated location, but a fingertip or stylus tip each have an inherent broadness which makes it difficult to know precisely which pixel is being indicated. In addition, when a portion directly beneath the fingertip or stylus tip is treated as the indicated location, the indicated location is hidden by the fingertip or stylus tip and cannot be directly observed. Moreover, because glass or the like has a thickness, there is distance and optical refraction between a touch screen surface and a display surface, causing parallax.
In this situation, a delicate input operation, such as selecting a specific pixel on the display screen or moving (for example, dragging) a selected location to a specific position with extreme accuracy, is difficult. There may be a belief that a high-performance, dedicated touch screen stylus can be created and used, but this would negate the convenience of a touch screen display. For example, when use alternates between a touch screen display and another device (for example, a joystick), the user is inconvenienced by picking up the dedicated touch screen stylus each time. There is no need to entirely eliminate use of a dedicated touch screen stylus, but providing a GUI enabling sufficiently fine input with a fingertip is preferred.
Japanese Patent Laid-open Publication No. H09-237157, Japanese Patent Laid-open Publication No. 2000-267808, Japanese Patent Laid-open Publication No. 2011-028524, and Japanese Patent No. 5132028 disclose several methods of improving operability of a touch screen display, but are all inadequate for extremely fine input operations, such as operations made on a pixel level.